Wash table, stainless steel

At the end of the 72-h cycle, the cathodes are removed from the cells, washed in hot water, and the brittie deposit, 3—6 mm thick, is stripped by a series of air hammers. The metal is then cmshed by roUs to 50-mm size and again washed in hot water. The metal contains about 0.034% hydrogen and, after drying, is dehydrogenated by heating to at least 400°C in stainless steel cans. Composition limits for electrolytic chromium are shown in Table 4. 

Industrially, the silver is recovered from either the wash water, or the bleach fix separately or from a mixture of the two using electrolysis employing a stainless steel cathode cylinder and an anode of stainless steel mesh. A typical wash solution composition contains silver (4 g L ), sodium thiosulphate (220 g L ), sodium bisulphite (22 g L ) and sodium ferric EDTA (4 g L ). At Coventry we have used a scaled down version of the industrial process employing 250 mL samples [46]. Electrolysis experiments were performed at ambient temperature with both wash and bleach fix solutions and in which the potential applied to the cathode and the speed of rotation of the cathode were varied. The sonic energy (30 W) was supplied by a 38 kHz bath. The results are given in Tab. 6.9. The table shows that the recovery of silver on sonication of the wash or bleach fix solutions is much improved especially if the electrode is rotated while ultrasound is applied. Yields with bleach fix (which contains ferric ions) are less since Fe and Ag compete for discharge (Eqs. 6.13 and 6.14). 

The obtained product was allowed to react with silica gel. The tertiary butyl protecting group was removed by the reaction of trifluoroacetic acid. The obtained product was washed thoroughly with 90% methanol followed by 100% methanol and dried at 60°C. The material was packed in appropriate stainless-steel columns. The ligand-exchange-based CSPs commercialized by different companies are given in Table 1. 

Before pyrolysis silicas were dried at 200°C and cooled to room temperature. Different amounts of organic precursors were deposited on dry silica (weight 5 g) to obtain carbon-silica adsorbents (carbosils) with different amounts of carbon deposits. Samples based on acenaphthene (Tables 1 and 2), acetylacetone and glucose (Table 3), were pyrolysed under static conditions in a stainless steel autoclave (0.3 dm3) at 773 K for 6 h. After reaction, all the prepared carbosils were washed in a Soxhlet apparatus with N,N-dimethylformamide and acetone, and then dried at 200°C. 

The initial reagents were held in a stainless steel autoclave, and the gaseous products were released through KOH soln. The liquid from the autoclave was poured onto ice, washed with H2O, held with lljO for 10 h, and distilled with steam. The organic layer was separated, dried (anhyd NUjSOj.), and distilled (yields see Table 18). 

In the case of (Sn)MCM-48 hexadecyltrimethylammonium hydroxide (0.1 mol), filmed silica (0.035 mol) and tin tetrachloride (from 5.5T0 to 4.5-10" mol) were used. The hydrothermal synthesis (samples denoted (Sn)MCM-48/HT) was carried out in Teflon-lined stainless steel autoclaves at 135 °C for 24 h [16]. Using microwave procedure the synthesis was performed at 135 C for 2 h (samples denoted (Sn)MCM-48/MW). All solid products were filtered, washed with deionized water, dried at 100 C and calcined at 550 °C. The prepared samples are listed in Table 2. 

In another research report by Yoshikaw and his group, mesoporous anatase Ti02 nanopowder was synthesized at 130°C for 12 h (see Table 2) [106]. Titanium (IV) butoxide (Ci6H3604Ti) was mixed in a 1 1 molar ratio with acetylacetone (CH3-CO-CH2-CO-CH3) to slowdown the hydrolysis and the condensation reactions. 40 ruL of distilled water was added in the solution and stirred at room temperature for 5 min. The solution was put into a Teflon-hned stainless steel autoclave while stirring and heated at 130°C for 12 h. The final product was naturally cooled to room temperature and washed with 2-propanol and distilled water. This was then dried followed by drying at 100°C for 12 h. The synthesized sample had a narrow pore size distribution with an average pore diameter of about 3 nm. The specific surface area of the sample was about 193 m /g. Mesoporous anatase TiOz nanopowders showed higher photocatalytic activity than the nanorods, nanofibers and commercial 7702 nanoparticles. 

MgCl2 (30g, S.A. 11 mVg) and internal donor were placed in a 1 L stainless steel vibration mill pot with 50 balls (25 mm ( )) under nitrogen and vibrated at room temperature for 30 h. The ground product (10 g as MgCl2) was reacted with TiCU (200 mL) in a 500 mL flask two times for two hours each at 110°C, followed by washing with n-heptane. The types of internal donor as well as the amount were varied to obtain a series of solid catalyst components. The Ti and donor contents analyzed are summarized in Table 1. 

Neill and Higgins determined distribution coefficients for Pu(HI) and Pu(IV) for several resins in sulfuric acid solutions. Their results-are shown in Table IV-28. They used Dowex-50 resin to demonstrate a process for recovering Pu from sulfuric acid decladding solutions which contain stainless steel. The Pu is normally trivalent in dilute sulfuric acid solutions, and is adsorbed from 0,5 M acid, scrubbed with 0.5 M sulfuric acid, washed with water to remove sulfate, and eluted with 6 N HNOg. The product Pu solution contained 5% of the original stainless steel materials, primarily iron and chromium. 

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